1. Field of the Invention
This invention relates to a connector for supplying a large electric power which is used for connecting a power source cable to another power source cable.
2. Related Art
The present invention is an associated invention of Japanese patent No. 3075717 owned by the present applicant. FIGS. 1 to 8 showing one embodiment of the present invention includes a basic construction of the Japanese patent No. 3075717.
The invention disclosed by the Japanese patent No. 3075717 includes a rod-like plug 2 for connecting a terminal of a first power source cable 1, a cylindrical receptacle 4 for connecting a terminal of a second power source cable 3, a first cylindrical casing 5 housing therein the rod-like plug 2 and a second cylindrical casing 6 housing therein the cylindrical receptacle 4.
It further includes a first cable inlet cylindrical portion 7 formed on a rear end of the first cylindrical casing 5, a second cable inlet cylindrical portion 8 formed on a rear end of the second cylindrical casing 6, an externally fitting cylindrical portion 13 formed on a front end portion of the first cylindrical casing 5 and an internally fitting cylindrical portion 14 formed on a rear end of the second cylindrical casing 6.
By fitting the internally fitting cylindrical portion 14 into the externally fitting cylindrical portion 13 and inserting the rod-like plug 2 into the cylindrical receptacle 4, the first and second power source cables 1, 3 are connected together.
In the power source cable connector of the Japanese patent No. 3075717, the externally fitting cylindrical portion 13 provided on the front end portion of the first cylindrical casing 5 and the internally fitting cylindrical portion 14 provided on the front end portion of the second cylindrical casing 6 are fitted to each other. An annular claw 29 provided on an inner peripheral surface of the front end of the externally fitting cylindrical portion 13 is engaged with an annular engagement groove 30 provided on an outer peripheral surface of a basal end of the internally fitting cylindrical portion 14 so that the first cylindrical casing 5 and the second cylindrical casing 6 are not disengaged from each other.
It is, therefore, an object of the present invention to provide a power source cable connector which is capable of better ensuring the disengagement effect, and which is capable of protecting the connection between the rod-like plug 2 disposed at the inside of the internally fitting cylindrical portion 14 and the cylindrical receptacle 4.
A second object of the present invention is to provide a power source cable connector which is capable of reinforcing the fluid tightness at the fitting portion between the externally fitting cylindrical portion 13 and the internally fitting cylindrical portion 14.
In the power source connector of the present invention, it is indispensable to provide a seal for ensuring the fluid-tightness at the cable terminal inlet portion on each rear end of the first and second cylindrical casings 5, 6. On the other hand, in the power source cable connector of the Japanese patent No. 3075717, a plurality of annular ribs 16 are juxtaposed on the inner peripheral surfaces of the first and second cable inlet cylindrical portions 7, 8 about a connector axis and in an axial direction. The annular ribs 16 are intimately contacted, in their compressed states, with the outer peripheral surfaces of the first and second power source cables 1, 3, thereby realizing a fluid tight condition.
A further object of the present invention is to provide a power source cable connector which is capable of better ensuring the effect of fluid tightness, and which is capable of stably retaining the connection even against a tensile force and a twisting force exerted to the first and second power source cables 1, 3.
According to the present invention, in the power source cable connector of the Japanese patent No. 3075717, a cylindrical protector is externally fitted to an outer periphery of the fitting portion between the externally fitting cylindrical portion and the internally fitting cylindrical portion. One end of the cylindrical protector is engaged with an outer peripheral surface at a basal portion of the externally fitting cylindrical portion, and the other end of the cylindrical protector is engaged with an outer peripheral surface at a basal portion of the internally fitting cylindrical portion. Thus, the effect of fluid tightness at the fitting portion is enhanced, and the connection is stably retained against a tensile force at the fitting portion. At the same time, the connection through a rod-like plug and a cylindrical receptacle is protected against an external impact at the fitting portion.
Moreover, the present invention keeps employing the construction in which a cylindrical protector is externally fitted to an outer periphery of a fitting portion between the externally fitting cylindrical portion and the internally fitting cylindrical portion. One end of the cylindrical protector is engaged with an outer peripheral surface of a basal portion of the externally fitting cylindrical portion, and the other end of the cylindrical protector is engaged with an outer peripheral surface of a basal portion of the internally fitting portion. Furthermore, an outer peripheral surface of the first cable inlet cylindrical portion is tightened with a tightening band, and an outer peripheral surface of the second cable inlet cylindrical portion is tightened with a tightening band. In addition, annular ribs juxtaposed on inner peripheral surfaces of the first and second cable inlet cylindrical portions tightly contact, in their compressed states, outer peripheral surfaces of the first and second power source cables to realize a fluid tight condition and to wholesomely maintain the connection between the power source cables 1, 3 against a tensile force and a twisting force exerted upon the respective cables 1, 3.
The cylindrical protector is fabricated of a split cylindrical body. After the cylindrical protector is attached to the fitting portion between the casings 5, 6, the split cylindrical body is tightened with a tightening band. Owing to this feature, the attachment can be made easily.